On Catch Discarding in Fisheries
This paper examines the economics of catch discarding in fisheries. To study this issue a simple dynamic fisheries model is constructed. On the basis of this model it is demonstrated that in a differentiated fishery discarding of catch may be socially optimal. The paper goes on to show that individual firms in a free access, competitive fishery employ the socially optimal discarding rule. In contrast, the individual transferable quota (ITQ) fisheries management regime tends to generate an excessive incentive for discarding catch. The problem, however, does not appear to derive from the ITQ system as such. Rather, it seems to depend on the imperfect application of the system to real fisheries. The concept of a discarding function is defined and it is shown that at least within the framework of the model employed the discarding function for an ITQ fishery dominates the one for free access, competitive fisheries. Numerical examples are provided. Finally, possible remedies of the discarding problem are briefly discussed.